DC9 landing pdx experienced near miss with another aircraft.

Attributes
ACN	581680
Time
Date	200305
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : pdx.airport
State Reference	OR
Altitude	msl single value : 7800
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : p80.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 30
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : p80.tracon
Make Model Name	De Havilland Canada Undifferentiated or Other Model
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : navigator
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 100 flight time total : 2800 flight time type : 700
ASRS Report	581680
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 500 flight time total : 9000 flight time type : 600
ASRS Report	581681
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance
Consequence	faa : investigated
Miss Distance	vertical : 750
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

At the time we were on the helns four arrival and had just crossed kratr intersection at 12000 ft, 300 KTS, when we were instructed by approach control to 'slow to 250 KTS, then descend to 7000 ft.' this was read back and we slowed, then descended as per the clearance. At approximately 7800 ft, we were advised that there was 'traffic below at 7000 ft and to maintain 8000 ft.' I immediately climbed back to 8000 ft. The pilot from aircraft Y flight at 7000 ft asked the controller what altitude we were cleared to and she read back 'I cleared aircraft Y to 10000 ft.' the response from aircraft Y was 'that was close.' we replied by saying that 'you cleared aircraft Y to 7000 ft.'

Original NASA ASRS Text

Title: DC9 LNDG PDX EXPERIENCED NEAR MISS WITH ANOTHER ACFT.

Narrative: AT THE TIME WE WERE ON THE HELNS FOUR ARR AND HAD JUST CROSSED KRATR INTXN AT 12000 FT, 300 KTS, WHEN WE WERE INSTRUCTED BY APCH CTL TO 'SLOW TO 250 KTS, THEN DSND TO 7000 FT.' THIS WAS READ BACK AND WE SLOWED, THEN DSNDED AS PER THE CLRNC. AT APPROX 7800 FT, WE WERE ADVISED THAT THERE WAS 'TFC BELOW AT 7000 FT AND TO MAINTAIN 8000 FT.' I IMMEDIATELY CLBED BACK TO 8000 FT. THE PLT FROM ACFT Y FLT AT 7000 FT ASKED THE CTLR WHAT ALT WE WERE CLRED TO AND SHE READ BACK 'I CLRED ACFT Y TO 10000 FT.' THE RESPONSE FROM ACFT Y WAS 'THAT WAS CLOSE.' WE REPLIED BY SAYING THAT 'YOU CLRED ACFT Y TO 7000 FT.'

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.